What is a Computer in Words?
A computer is an electronic machine operating under the control of instructions stored in its own memory that can accept data input, manipulate the data according to specified rules, process, produce results, output, and store the results for future use. Technically, a computer is a programmable machine, which means it can execute a list of programmed instructions and respond to new instructions it is given.
Historical Perspective on the Term 'Computer'
Traditionally, a computer was a person who performed repeated numerical calculations. The results of these calculations were then combined to produce a solution to a larger problem. Starting in the 19th century, research into calculating machines gathered pace, and by the time of the Second World War, these had become electronic rather than mechanical. This shift led to such machines being known by analogy with the human occupation as Computers. The term was used across various languages, for example, Ordinateur in French, Computer in German, Ordenador in Spanish, and Datamaskin in Danish.
As the Second World War ended, machines had developed into completely general devices, what came to be known as programmable or stored programme machines. In modern usage, a computer is an electronic device that follows programmed instructions to perform calculations. The nature of the machine enables it to do this rapidly, allowing for the tackling of extremely complex problems in a reasonable time.
The Nature and Functionality of Modern Computers
Although the mechanism is entirely arithmetic, it is possible to encode a vast range of problems as a mathematical representation. This makes it possible for modern computers to perform a wide variety of tasks, such as generating designs for machine parts, mapping landscapes, handling music or language, and indexing vast amounts of data, among others. Modern computers surround the arithmetic cores with storage, both short-term, long-term, and archival, as well as input and output devices used by the operator. They also have digital or analogue input/output channels for machine control. A whole bunch of devices often called peripherals are also associated with computers.
Evolution of Computer Design
19th-century calculating machines eventually transformed into fully programmable electronic machines. Mechanical, single-purpose computers persisted for decades. I worked on Decca true-plot radars, which used wheels to resolve ship’s speed and heading into x-y coordinates. Ballistic computers for artillery were mechanical even in the 1980s and, for all I know, still are. This evolution shows how computing has advanced over time, with machines becoming more versatile and capable of handling a broader range of tasks.
Throughout the 20th and 21st centuries, computers have continued to evolve, improving in speed, capacity, and functionality. Today, they are integral to many aspects of modern life, from personal computing and smartphones to complex scientific research and AI-driven applications.
Understanding the nature of computers and their historical development can provide valuable insights into their role in society and how they continue to shape the future.